The Toxicologist - Society of Toxicology

2425 EFFECTS OF FUMONISINS IN ETHANOL
PRODUCTION.
E. Bilsten and G. Munkvold. Plant Pathology, Iowa State University, Ames, IA.
Fumonisins are common maize contaminants produced by a number of fungal
species in the genus Fusarium; consumption of fumonisins leads to a variety of
detrimental health effects in livestock. Dried distiller’s grains and solubles (DDGS)
are a co-product of ethanol production used for animal feed and revenue generated
from their sale is essential to profitability in the ethanol industry. Studies conducted
in 2007-2009 showed fumonisins were more concentrated in DDGS as compared
with the original grain, though the degree of concentration varied. The Grain
Inspection, Packers and Stockyards Administration (GIPSA) has approved quality
testing methods for fumonisin concentrations in grain intended for animal feed, including
testing by ELISA methods. Analysis of fumonisin contaminated grain (and
consequent DDGS) was performed using both a GIPSA-approved ELISA test kit
and HPLC-fluorescence detection of the naphthalene-2,3-dicarboxalehyde (NDA)
derivatized fumonisin molecule. There was a close correlation between ELISA and
HPLC results (R = 0.97) but ELISA tended to underestimate fumonisin concentrations.
Under-estimation of fumonisins by ELISA testing could result in feeding animals
more highly contaminated grain than is considered safe. Use of fumonisincontaminated
maize for ethanol production may result in decreased quality and
marketability of co-products, and may also impact fermentation efficiency and subsequent
ethanol yields.
2426 COMBINATIVE TOXICITY OF MYCOTOXIN MIXTURES
IN ANIMALS AND HUMAN CELLS.
G. Qian, L. Tang and J. Wang. Environmental Health Science, University of
Georgia, Athens, GA.
Mycotoxins are naturally occurring toxic fungal metabolites, which have caused the
tremendous economic loss worldwide and are etiological agents of a variety of animal
and human toxicoses. The aflatoxins, certain tricothecenes, and fumonisins are
ubiquitous food contaminants and have been shown to be carcinogenic and/or teratogenic
in experimental animal models. Because of their potent toxicities in animal
and humans, some mycotoxins are candidates for use as biological warfare
agents, for example, aflatoxin and T-2 toxin have been known to be weaponized
and may be available for use as terrorist attack(s); therefore, there is an urgent need
to understand the combinative toxicity of these toxin mixture(s). In this study,
combinative toxicities of aflatoxin B1 (AFB1), T-2 toxin (T-2), and fumonisin B1
(FB1) were tested in F-344 rats, mosquitofish (Gambusia affinis), and human hepatoma
cells (HepG2) and bronchial epithelial cells (BEAS-2B). Preliminary experiments
were conducted in order to assess the acute toxicity/cytotoxicity and obtain
LD50, LC50 and IC50 values for individual toxins in each model, respectively.
This was followed by testing combinations of mixtures containing AFB1, T-2, and
FB1 to obtain LD50, LC50 and IC50 values for the combination in each model.
All models demonstrated a significant dose response in observed parameters to
treatment. The potency of the tri-toxin mixture was gauged through the determination
of the combinative toxicity index (CTI=estimated LD50, LC50 and
IC50/measured LD50, LC50 and IC50). Additive toxic effects were observed in rat
for the tri-toxin mixture (CTI=1.0). Synergistic toxic effects were found in mosquitofish
with the CTI of 2.8. Additive to synergistic toxic effects were observed in
HepG2 cells (CTI=1.8) and BEAS-2B cells (CTI=2.0) for the tri-toxin mixture.
These results will provide foundational knowledge in future studies on long-term
combinative toxic effect and risk assessment of health effect of co-exposure to these
mycotoxin mixtures. (Supported by the research contract, DAAD13-02-C-0070,
from DOD).
2427 MYCOTOXINS MULTI-CONTAMINATION OF
PRESCHOOL AGE CHILDREN IN BENIN:
PRELIMINARY STUDY IN THE ZOU REGION.
E. E. Creppy 1 , J. Tabe-Dumond 1, 2 , S. Moukha 1, 2 and B. Sangare-Tigori 1, 3 .
1 Toxicology, University Bordeaux 2, Bordeaux, France, 2 Toxicology, University
Bordeaux 2, Bordeaux, Gironde, France and 3 Toxicology Department, University of
Abidjan, Abidjan, Côte d’Ivoire.
The natural occurrence of mycotoxins in food and foodstuffs is widespread, and of
human health concern, especially in tropical regions. In an attempt to confirm mycotoxins
multi contamination, 25 samples of cornstarch and mixed foods intended
for children consumption, (apparently healthy children, n=20) and (malnourished
children n=49) from the Zou-Region nutrition recovery centres in Benin were assayed
for (ochratoxin A, aflatoxins, zearalenone, T-2 toxin, HT-2 toxin, nivalenol,
deoxynivalenol and fumonisins) by LC-MS-MS. All the samples were contaminated
by several mycotoxins, with concentrations ranging from 0.5 – 2879.2 μg/kg
for aflatoxins, 50 – 1290 μg/kg for trichothecenes, 0.5 – 1360 μg/kg for fumonisins,
0.5 – 4.3 μg/kg for ochratoxin A and 5 – 22 μg/kg for zearalenone.
Ochratoxin A (OTA), known to be nephrotoxic, immunosuppressive and carcinogenic
is a mycotoxin produced by fungi of Aspergillus and Penicillium genera. It
has been assessed in blood by enzyme immunoassay after purification using immunoaffinity
columns followed by confirmation by HPLC-Fluorimetric quantification
and taken as a biomarker of exposure of children to all the above mentioned
mycotoxins. When ingested, this toxin has a bioavailability of about 50%. All children
tested are contaminated, 100% of well nourished ones show OTA blood concentrations
from 6.9 to 54 μg/l, whereas, malnourished children showed significantly
lower concentrations (p= 0.0051), in the range of 0.3 – 48.4 μg/l and a mean
value of 20.8 μg/l. Ochratoxin A found in the children’s blood fully reflect OTA
contamination of their diet, and is a biomarker of other mycotoxins also found in
foodstuffs. The present data confirm mycotoxins multi contamination in west-
Africa and show for the first time that trichothecens and zearalenone are present in
foodstuffs in Benin and may be worsening the adverse effects of aflatoxins and
ochratoxins in children of preschool age in Benin.
2428 PYRROCIDINE A TOXICITY IN MICE.
S. Hooser 1 , C. R. Wilson 1 , G. N. Burcham 1 , W. M. Haschek-Hock 2 and D. T.
Wicklow 3 . 1 Animal Disease Diagnostic Laboratory, Purdue University, West Lafayette,
IN, 2 Department of Pathobiology, University of Illinois, Urbana, IL and 3 Bacterial
Foodborne Pathogens and Mycology Research Unit, USDA ARS, Peoria, IL.
Pyrrocidines A and B are metabolites produced by the fungus Acremonium zeae, a
common seedborne endophyte of corn. Pyrrocidine A exhibits potent activity
against Gram-positive bacteria, including drug resistant strains, and displays significant
activity against Candida albicans, as well as major stalk and ear rot pathogens
of corn. Pyrrocidines have been detected in visibly molded corn subjected to
drought and temperature stress and are consistently produced in A. zeae isolates
from corn grown in warmer regions. A. zeae is being evaluated for its potential application
as a biocontrol agent in protecting corn plants from virulent pathogens.
Thus, information is needed to determine whether or not increased pyrrocidines in
corn would pose a safety risk. In 2007 the Haschek laboratory reported that the cytotoxicity
of pyrrocidine A to human HepG2 cells was more potent than the
known Fusarium mycotoxins, deoxynivalenol, fumonisin B1, moniliformin and
zearalenone. However, pyrrocidine A toxicity was not observed in mice at doses up
to 10 mg/kg body weight based on clinical signs, organ weights, and gross and microscopic
lesions. The studies reported here evaluated higher doses in mice. Adult,
male, Swiss-Webster mice were administered pyrrocidine A (n = 5/group) at 0
(DMSO control), 10, 100 or 250 mg/kg (i.p.). Pyrrocidine A at 10 mg/kg was not
lethal and did not cause clinical signs, while 100 mg/kg and 250 mg/kg resulted in
death within 24 hours. Pyrrocidine A at 25 mg/kg and at 50 mg/kg caused death in
1 mouse in each group within 12 hours. No significant gross or histological lesions
were seen. This study indicates that at doses of 10 mg/kg (i.p.), pyrrocidine A does
not cause acute toxicity but can be fatal at doses of 25 mg/kg or greater.
2429 FOOD ANTIOXIDANTS HAVING NO, OR WELL-
SPECIFIED, LEVELS OF ESTROGENIC ACTIVITY (EA).
C. Z. Yang 1 and G. Bittner 1, 2, 3 . 1 CertiChem, Inc., Ausin, TX, 2 PlastiPure, Austin,
TX and 3 University of Texas, Austin, TX. Sponsor: R. Tice.
Food antioxidants (AOs) have for decades been added in various combinations (formulations)
to foodstuffs primarily to preserve food quality and more recently for
health benefits such as reducing the incidence of some cancers, brain damage, and
cell ageing. Chemicals such as AOs having agonist or antagonist EA at concentrations
used in foodstuffs (mM to μM) often have adverse effects on mammals, including
humans. Fetal or juvenile mammals are especially sensitive to effects of
chemicals having EA at very low dosages (nM to pM concentrations). Using a recently-developed
sensitive and reliable robotic assay, we show that many, synthetic
or natural, commonly-used food AOs have significant EA and that many other,
synthetic or natural, less-commonly-used AOs do or do not have EA. For example,
BHA and BHT have easily detectable agonist EA whereas propyl gallate has easily
detectable antagonist EA. Using such data, CertiChem is devising food AO formulations
having no detectable EA—or well-specified levels of EA. The creation of
such formulations is important because some human populations such as pregnant
mothers, infants and juveniles should almost-certainly not ingest foodstuffs containing
AO formulations having easily-detectable levels of EA. Conversely, some
conditions in adult humans (e.g., menopause, some cancers or abnormalities of the
prostate) would probably be ameliorated by foodstuffs containing AO formulations
having well-specified levels of EA. Supported by NSF SBIR Phase I 0912601 and
NIH SBIR44ES014806.
SOT 2011 ANNUAL MEETING 521